Telephone system.



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TELEPHONE SYSTEM.

APPLIOATION FILED MAR.29,1905.

2 SHEETS-SHEET 2.

HENRY LINTON REBER, OF ST. LOUIS, MISSOURI.

TELEPHONE SYSTEM.

Specification of Letters Patent.

Patented Dec. 18, 1906.

Application filed March 29,1905. Serial N0. 252,655-

To @ZZ whom it may concern:

Be it known that I, I-IENRY LINTON REBER, a citizen of the UnitedStates, residing at St. Louis, in the State of Missouri, have inventednew and useful Improvements in Telephone Systems, of which the followingis a full, clear, concise, and exact description, reference being had tothe accompanying drawings, forming a part of this specification.

My invention relates to improvements in those features oftelephone-exchanges which are involved in making trunking connectionsbetween the various central offices or switchboards of the exchange, myobject in general being to provide means for improving` the service byquickening the same and rendering it more certain and satisfactory thanheretofore and to reduce the equipment, as well as the number ofoperators required.

In the exchanges of our larger cities the greatest number of calls isfor trunking connections, this in some instances rising as high asseventy-iive per cent., and at the same time such connections are themost difficult to make and the most liable to errors, due to the factthat at least two sets of operators are involved in initiating andcompleting such connections, with the consequent necessity forcommunication back and forth between them and the liability formistakes. It is apparent, therefore, that any improvement which resultsin the betterment of this class of service in the respects mentioned,particularly those of increasing the speed, is most desirable, and thisis true even though only a small fraction of a second per call isgained, since in the aggregate the saving in time is large. It isevident also that an increased speed of establishing such connectionsresults in a less number of operators, since each can do more work andhandle a greater number of calls, and a smaller amount of equipment isnecessary, since the periods of delay between conversations are reduced.

In the larger exchanges, as is well known, it is common to provideseveral central offices each in itself having a large multipleswitchboard, and these ollices are connected together by trunk-circuitsto extend the talking-circuits through from one switchboard to theother. In addition the operators are provided with circuits independentof the trunk-circuits, commonly known as order-wires or order-wirecircuits, to enable them to communicate with each other for the purposeof properly establishing the talking connections between the subscribersof the different switchboards. In the ordinary arrangement of such largemultiple switchboards the multiple jacks are distributed before theoperators in the upper part of the board and the answering-jacks of thesubscribers lines are placed upon the lower portion of the board. Thetrunk-circuits terminate at one ofiice in multiple jacks distributedthroughout the switchboard before the operators, these jacks beingusually placed between the subscribers answering and multiple jacks, andat the other oflice they terminate in connecting cords and plugs, whichare usually placed upon separate sections of the switchboard, known asthe incoming-trun section, and upon which sections the subscribers'lines of that office are extended through to multiple jacks arrangedsimilarly to the corresponding jacks in the ordinary multiple sections.These trunk-circuits are designated as outgoing trunks at the firstswitchboard or oHice, where they are provided with multiple jacks, andas incoming trunks at the other switchboard or oiiice, at which theyterminate in connecting-plugs. The first ofiice is often spoken of asthe A office, and the second office as the B office, and thecorresponding operators are termed A operators and B operators. Thisarrangement of the apparatus for establishing through communicationsbetween widely-separated subscribers and central ofiices is the resultof years of experience and has proven the best for satisfactory andquick service. The terms thus applied to the offices, apparatus, andoperators are the result of this arrangement of the trunks and themethod of handling the trunking connections, since calls are iirstreceived by the A operators at the A oflice, are then transmitted to theB operators at the B ofiice, and by the latter are completed byconnecting the incoming-trunk circuits with the proper telephone-linecircuits at said office. Such connections therefore maybe said to beinitiated at theA oiiice and completed at theB oflice. In order thatthese two sets of operators may expeditiously perform their work with asfew mistakes and as little confusion as possible, a prescribed code ofcommunication between them is followed, that usually employed in largeor busy oflices being as follows: As soon as anA operatorreceives anorder from a call- IOO IIO

ing subscriber for a connection with a party whose line appears upon adifferent switchboard she communicates with the B operator at the saidboard and informs her of the line wanted. The B operator immediatelyinforms the A operator of the proper trunk to be used for the connectionand immediately completes the connection by inserting the plug of thetrunk which has been designated into the jack of the called line. The Aoperator at once establishes the connection between the callingsubscribers line and the trunk through the medium of her cord-circuit.These acts thus serve to establish a complete talking-circuit for thesubscribers. In this connection I have omitted the steps of testing thecondition of the wanted line and calling the subscriber, since these maybe carried out in any well-known manner.

For convenience and speed in establishing communications between the twosets of operators each order-wire terminates in the receiver of a Boperator having in charge a certain number of incoming trunks. At the Aoffice these order-wires extend before all of the operators, and each isprovided with suitableswitches or keys, known as order-keys, to enableher to readily connect her headtelephone with any of the order-wires.Thus when an A operator wishes to communicate with a B operator shedepresses an order-key to connect her telephone with the order-wireleading directly to the B operators telephone. These order-keys areusually placed in a row or strip upon the key-shelf of the switchboardat each operators position. The operators are therefore required tolistenin upon the order-wires-that is, to connect their head-telephoneswith the order-wires and listen for a moment to determine whether or notthe B operators are engaged. If after thus listening an order-wireislfound to be busy, a second key is depressed, and so on until an idleB operator is found to take charge of and complete the connection at theB board. This results in delay, since the calling subscriber is waitingfor the completion of his connection and is frequently the cause ofmistakes on account of the A operators failure to listen long enough,and which results in a confusion of orders and the establishment ofwrong connections.

The object of my invention is to provide means for enabling the Aoperators to select the idle B operators without delay and confusion. Incarrying out my invention I provide means for indicating to the Aoperators the idle or busy condition of the order-wires, whereby any Aoperator is enabled to immediately select an order-wire and communicatewith a B operator who is idle and free to at once complete theconnection.

In one form of the invention a signal is provided in association witheach order-key, so that under some conditions of use a glance issufficient to enable the A operators to immediately put themselves incommunication and the number of trunk-circuits and orderwires, as wellas switchboard equipment,

may be reduced, since they are enabled to handle more calls than informer arrangements.

The invention is conventionally illustrated in the accompanyingdrawings, in which the same reference characters are used throughout toindicate the like parts, and in which- Figure l. is a diagram of atelephone-exchange, indicating the apparatus and circuits ordinarilyinvolved in tru'nking connections, and Fig. 2 is a diagram of theorder-wire circuits only involved in such an exchange and showing indetail the invention applied thereto.

Referring to Fig. 1, L and L2 indicate two subscribers lines terminatingupon the multiple switchboard at the A office, and L3 and L1 indicatemultiple sections of telephoneline circuits terminating upon theincomingtrunk section of the B office. T and T2 indicate thetrunk-circuits extending between the A and B offices, and O and 02indicate the order-wire circuits extending between the same offices. Thelines L and L2 are each furnished with an answering-jack J and multiplejacks, such as J 2 and J 3, in any number upon the various sections ofthe multiple switchboard at the A office. In like ICO manner thetelephone-lines L3 and LL are each provided with multiple spring-jacks Jl and J5 upon the incoming-trunk section of' the switchboard at the Boffice. The trunks T and T2 at the A office, where they are termedoutgoing trunks, are furnished with similar multiple spring-jacks JG,J7, and JS upon the various sections of the switchboard, and at the Boffice, where they are known as lincoming trunks, they are provided withcords and connectingplugs P upon the incoming-trunk sections.Cordcircuits C are provided in any number at the various sections andoperators positions of the multiple switchboard at the A office toenable the operators to establish connections for conversationalpurposes between the various subscribers lines and between thesubscribers lines and the outgoing trunks. At the A office theAorder-wires O and O2 extend past the various operators positions, eachoperator being provided with a strip of order-keys 7c k2 to enable herto readily conrio nect her head-receiver 1' with any of the saidorder-wires, while at the B office said orderwires terminate in thehead-receivers r2 of the B operators at the incoming-trunk sections, oneterminating in one operators receiver and the other in another. It willbe understood that this diagram is intended merely to conventionallyillustrate the usual exchange arrangement so far as the same enters intomy invention without reference to the details of the various parts orthe illustration of the features not directly concerned in the saidinvention, and, while but three sections and three operators positionsof the multiple switchboard are indicated and but two sections and twooperators positions at the B oflice are shown, that in practice thesemay comprise as many sections and positions as desired, and thatmanymore trunks would be assigned to each incoming operator than isshown in the diagram. The means for signaling in connection with thelines, cord-circuits, and trunk-circuits are entirely omitted, as notentering into the present matter, and for the same reason no attempt hasbeen made to illustrate either a common battery or magneto-exchange,although as a matter of fact the larger eX- changes to-day are nearlyall of the commonbattery type.

ln the ordinary operation of the system a call coming in over the line Lis received at the first section and the operator inserts theanswering-plug p of one of her cord-circuits C into the answering-jack Jof the callingline and connects her head-telephone therewith by means ofthe usual listening-key to receive the order from the callingsubscriber. Upon 'finding that a connection is wanted with a lineterminating at the B oflice-for instance, with the line L3-the operatordepresses one of the order-keys k or k2 to connect her head-telephonewith one of the order-wires O or O2 to thus put herself in communicationwith the corresponding B operator at the said other office. At the sametime she informs the latter operator that a certain line is wanted, andthe B operator immediately informs the A operator to use a certaintrunk, at the same time picking up the connecting-plug of thel trunkdesignated and, if necessary, testing the condition of the wanted lineand, if idle, inserting the plug into the multiple jack of the line L3on her section of the switchboard. If the A operator has depressedorder-key k2, she has connected her telephone with the operator at thefirst incoming-trunk section at the B office, and the plug P of thetrunk T is taken up by the latter operator and inserted in the jack J4of the wanted line L3. Meanwhile the A operator has inserted the plug p2of the cord-circuit with which she answered the call of the subscriberinto the jack J of the trunk T. The through talking-circuit between thetwo switchboards and the two subscribers lines is thus established.

It is evident that the A operator is unableto tell before depressing oneof the order-keys and listening-in whether or not the B operator isbusy, and hence may be required to take sufficient time to listen-in tothis extent on several of the order-wires before 'finding an unengaged Boperator. My invention is designed to obviate the delay this caused bythe A operator in selecting an idle B operator and to provide meanswhereby such delays are largely eliminated and the operators are enabledto immediately select'the idle B operators. One means for accomplishingthis is indicated more clearly in Fig. 2, in which the trunk-circuitsand subscribers lines are omitted for the sake of clearness. In thisligure it will be seen that the order-wires O and O2 extend from the Aoflice at the left to the B oflice at the right. At the latter oilicethey terminate in the head-receivers r2 of the operators, while at theformer oiiice they pass successively through the various operatorspositions. The head-telephones r of the A operators are adapted to beconnected with the order-wires through the medium of the order-keys 7c7a2, which when depressed connect their springs 2 and 3, ljoined to thesaid order-wires, with their contacts 4 and 5, which are connected withthe said head-receivers of the operators. Each of these keys has anadditional spring 6 connected with ground, the normal contact 7 of whichspring is connected upon one side with a suitable signal S, which may bein the form of a small incandescent lamp, the opposite terminal of whichsignal is connected with a common conductor 8, leading from one of thenormally open contacts of a relay R, the other of which contacts isjoined to the live pole of a battery B. The alternate or normally opencontact 9 of each of said keys is connected through a second common leadl0 with one terminal of the winding of the relay R, the other terminalof which is likewise joined to the live ole of the battery B. Associatedwith the reys k2 throughout the series of operators7 positions aresimilar signals S2, which are connected in a manner similar to the keyslc with the leads l l and l2, extending from the relay R2, connected,like the relay R, to the battery B. It will be observed that normallythe said signals- S and S2 are connected upon one side to ground bymeans of the closed contacts 6 and 7 ofthe order-keys k k2, Sac. Vhenthe corresponding relayR or R2 is operated, therefore, said lampsreceive current from battery B and are lighted. These relays areoperated whenever any order-keyl associated with their signaling-circuitis depressed. For instance, depressing any of the keys c serves todisconnect the spring 6 from the contact 7 and to connect it with thecon- IOO IIO

tact 9. This has the effect of grounding the conductor l0 and permittinga flow of current from the battery B, through the winding of the relay Rand over the conductor 10, and through the grounded spring 6 of thedepressed key, which results in the energization of said relay R,thereby lighting all the lamps S associated with the other order-keys kof the same order-wire. These lamps on being lighted indicate to theoperators at the other positions that the said order-wire is in use andthat the B operatorwith which it is connected is engaged. Tt will beunnecessary, therefore, for them to even listen-in upon said order-wire,and when desiring a connection with the B operators they have only todepress any of the order-keys in connection with which the signals arenot shown. The depression of any key k2 likewise operates relay R2 andlights the lamps or operates the signals S2 associated with the otherkeys 762. These signals S S2 may be placed in the switchboardimmediately at the sides of the corresponding keys, in the keys, or inany other desired location and may be lamps, as shown, or annunciators,or any desired type. ln case the invention be applied to a commonbatteryexchange the battery B may be one of the main batteries at the A office.

If for any reason a B operator is unable to attend to the calls comingin over her orderwire, a key 7L is provided therein which when operateddisconnects the sam e from her headtelephone and connects it with somedevice arranged to impress thereon a distinctive current or signal, suchas the ordinary busy signal device found in most large exchanges or aphonographic device. This when so connected serves to 0ive the Aoperators a distinctive signal in their receivers whenever they depressan order-key. They are thus notified that the order-wire is not in useat the B ol'lice. Obviously any other signaling means might be employedin place of this busy signal. The signals S S2, &c., might be operatedfrom the B ol'iice also, but the arrangement shown is preferred. It isevident that with this arrangement the selection of the B operator ishastened, since the busy signal is at once given and the A operator doesnot need to pause for any length of time to determine the condition ofthe circuit, but, on the contrary, is at once informed of suchcondition. This key 7L at the B oflice may be made use of in caseorder-wires from different offices are connected with the same Boperator and the Work at times becomes too heavy for theB operators tohandle. Then the keys h in the order-wires extending to-some of theofiices may be operated to prevent so many calls from coming in, therebyenabling the operators to satisfactorily handle the calls from the otherol'lices. Again, it maybe desired during certain times of the day torelieve some of the B operators entirely because a less number can dothe work, and in such cases thevkeys h may be depressed. The signals Sand S2 and busy-signal keys 7i are likewise indicated in dotted lines inFig. 1.

It is thus apparent that the invention results in increasing the speedwith which trunking connections may be established, reduces theliability for errors, and decreases the number of operators employed, aswell as the number of trunk-circuits, order-wires, and switchboardequipment required. Nhile only one specific means has been. shown anddescribed for accomplishing these results, it is evident that theinvention is in no wise so limited, for obviously many variations andmodifications may be made therein without departing from the scope orprinciple of the same. Hence l do not wish to be limited to the speciiicform so shown and described.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, isn

l. In a telephone-exchange system, the combination with an A switchboardand a B switchboard, of trunk-circuits extending between saidswitchboards, operators devices at each switchboard to enableconversational connections to be established between the lines of saidswitchboards through the medium of said. trunk-circuits, order-wirecircuits also extending between the said switchboards and havingmultiple terminals at the A board, to provide means for communicationbetween the A and B operators, and means associated with the order-wirecircuits to enable the A operators to instantly pick out the idle Boperators.

2. In a telephoneexchange system, the combination with an A switchboardand a B switchboard, of trunk-circuits extending between saidsudtehboards, operators devices at each switchboard to enableconversational connections to be established between the lines of saidswitchboards through the medium of said trunk-circuits, order-wirecircuits multipled at the A board also extending between the saidswitchboards to provide means for communication between the A and Boperators, and indicating means associated with the orderfwire circuitsto enable the A operators to instantly select the idle B operatorsY 3.In a telephone exchange system, the combination with an A switchboardand a B switchboard, of trunk-circuits extending between saidswitchboards, operators devices at each switchboard to enableconversational connections -to be established between the lines of saidswitchboards through the me` dium of said trunk-circuits, order-wirecircuits also extending between the said switchboards to provide meansfor communication between the A and B operators, said ordercircuitsextending before a plurality of A operators, and means associated withthe orden IOO TIO

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combination with an A switchboard and a B switchboard, of trunk-circuitsextending between said switchboards, operators devices at eachswitchboard to enable conversational connections to be establishedbetween the lines of said switchboards through the medium of saidtrunk-circuits, order-wire circuits each having a plurality of Aterminals also extending between the said switchboards to provide meansfor communication between the A and B operators, and means associatedwith the order-wire circuits whereby the A operators are enabled toselect the idle B operators without the necessity of listening in. 5. Ina telephone-exchange system, the combination with an A switchboard and aB switchboard, of trunk-circuits extending between said switchboards,operators devices at each switchboard to enable conversationalconnections to be established between the lines of said switchboardsthrough the medium of said trunk-circuits, order-wire cir-l cuits havinga plurality of A terminals also extending between the said switchboardsto provide means for communication between the A and B operators, andbusy-signaling means associated with said order-wires to inform the Aoperators of the idle or busy con'- dition of said wires.

6. In a telephone-exchange system, the combination with an A switchboardand a B switchboard, of trunk-circuits extending betweensaidswitchboards, operators devices at each switchboard to enableconversational connections to be established between the lines of saidswitchboards through the medium of said trunk-circuits, order-wirecircuits passing before a plurality of A operators also extendingbetween the said switchboards to provide means for communication betweenthe A and B operators, and means associated with the order-wire circuitsto indicate to the A operators the idle or busy condition of saidorder-wires.

7. In a telephone-exchange system, the combination with an A switchboardand a B switchboard, of trunk-circuits extending between saidswitchboards, operators devices at each switchboard to enableconversational connections to be established between the lines of saidswitchboards through the medium of said trunk-circuits, order-wirecircuits passing through a plurality of A operators7 positions and alsoextending between the said switchboards to provide means forcommunication between the A and B operators, and means associated withsaid orderwires to indicate their idle or busy condition.

S. In a telephone-exchange system, the combination with an A switchboardand a B switchboard, of trunk-circuits extending between saidswitchboards, operators devices at each switchboard to enableconversational connections to be established between the lines of saidswitchboards through the medium of said trunk-circuits, order-wire cir-lcuits also extending between the said switchboards to provide means forcommunication between the A and B operators, said orderwires passingbefore the various operators at the A board and connected each with anoperators telephone at the B board, order-keys before the operators atthe A board to enable them to connect their telephones with any of theorder-wires, and busy signals for said order-wires whereby whenever oneis in use the fact is indicated at the various positions, substantiallyas described.

9. In a telephone exchange system, the combination with an A switchboardand a B switchboard, of trunk-circuits extending between saidswitchboards, operators devices at each switchboard to enableconversational connections to be established between the lines of saidswitchboards through the medium of said trunk-circuits, order-wirecircuits also extending between the said switchboards to provide meansfor communication between the A and B operators, said orderwires passingbefore the various operators at the A board and connected each with anoperators telephone at the B board, order-keys before the operators atthe A board to enable them to connect their telephones with any of theorder-Wires, and busy signals for the said order-wires whereby wheneveran order-key is operated at one position, the corresponding signals aregiven at the other positions, substantially as described.

10. In a telephone-exchange system, the combination with an Aswitchboard and a B switchboard, of trunk-circuits extending betweensaid switchboards, operators devices at each switchboard to enableconversational connections to be established between the lines ofsaidswitchboards through the medium of said trunk-circuits, order-wirecircuits also extending between the said switchboards to provide meansfor communication between the A and B operators, said orderwires passingbefore the various operators at the A board and connected each with anoperators telephone at the B board, order-keys before the operators atthe A board to enable' IOO IIO

them to connect their telephones with any of connections to beestablished between the lines of said switchboards through the medium ofsaid trunk-circuits, order-wire circuits also extending between the saidswitchboards to provide means for communication between the A and Boperators, said order wires passing before the various operators at theA board and connected each with an op erators telephone at the B board,order-keys before the operators at the A board to enable them to connecttheir telephones with any of the order-wires, and means associated withthe order-wire circuits whereby whenever an order-wire is in use or notin condition for use a busy-signaling indication is given at the Aswitchboard.

12. In a telephone-exchange system, the combination with an Aswitchboard and a B switchboard, of trunk-circuits extending betweensaid switchboards, operators devices at each switchboard to enableconversational connections to be established between the lines of saidswitchboards through the medium of said trunk-circuits, order-wirecircuits also extending between the said switchboards to provide meansfor communication between the A and B operators, said orderwires passingbefore the various operators at the A board and connected each with anoperators telephone at the B board, orderkeys before the operators atthe A board to enable them to connect their telephones with any of theorder-wires, and means whereby when an order-wire is thrown out of useat the B office a distinctive signal is made possible to the operatorsat the A oflice.

13. In a telephone-exchange system, the combination with an Aswitchboard and a B switchboard, of trunk-circuits extending betweenthese boards, operators devices at the boards to connect the linesthereof with said trunk-circuits, order-wires between the boards topermit communication between the operators, and means at the B board toplace said order-wires in condition. to distinctively test busy,substantially as described.

14. In a telephone-exchange system, the combination with branchexchanges, of a multiple switchboard at one of the branch exchanges,trunk-circuits extending from said switchboard to the other branchexchange, said trunk-circuits extending through a plurality of operatorspositions at said multiple board, connecting means at each branchexchange to connect said trunks with the subscribers lines, order-wirecircuits extending between the branch exchanges and passing through theoperators positions at said multiple board, means to enable theoperators at the multiple board to connect their telephones with any ofsaid order-circuits, and means whereby when one of the operators at themultiple board has connected her telephone with one of the orderwirecircuits, said circuit indicates busy at the other operators positionsat such board.

15. In a telephone-exchange system, the combination with branchexchanges, of a multiple switchboard at one of the branch exchanges,trunk-circuits extending from said switchboard to the other branchexchanges, said trunk circuits extending through a plurality ofoperators positions at said multiple board, connecting means at eachbranch exchange to connect said trunks with the subscribers lines,order-wire circuits extending between the branch exchanges and passingthrough the operators positions at said multiple board, operatorslistening-keys at each operators position at the multiple board toenable the operators to connect their telephones with any of saidorder-circuits, signals associated with said order-keys, and meanswhereby when one of the order-keys is depressed at the operatorsposition to connect her telephone with an order-circuit, the signalsassociated with the order-keys for that same order-circuit at the otheroperators positions are operated to ine dicate that the saidorder-circuit is busy.

16. In a telephone-exchange system, the combination with branchexchanges, of a multiple switchboard at one of the branch exchanges,trunk-circuits extending from said switchboard to the other branchexchanges said trunk-circuits extending through a plurality of operatorspositions at said multiple board, connecting means at each branchexchange to connect said trunks with the subscribers lines, order-wirecircuits extending between the branch exchanges and passing through theoperators positions at said multiple board, a signaling-circuitassociated with each order-wire circuit in the multiple board, operatorslistening-keys at the multiple board to enable the operators to connecttheir telephone with said orderwire circuits, a signal for eachorder-key con nected with the corresponding signaling-circuit, and meanswhereby the depression of any listening-key operates the signalsassociated with the other order-keys of the same order-circuit.

In witness whereof I have hereunto subscribed my name in the presence oftwo wite HGSSQS.

H. LINTON REBER. Vitnesses JAMES HARRIsoN, JOHN M. STUART.

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